[PATCH v2 2/3] gdb: factor out printing a table of solibs for info sharedlibrary

Guinevere Larsen
2025-04-09T20:46:09Z

The next patch will add a new command that will print libraries in a
manner very similar to the existing "info sharedlibrary" command. To
make that patch simpler to review, this commit does the bulk of
refactoring work, since it ends up being a non-trivial diff to review.

No functional changes are expected after this commit.
---
gdb/solib.c | 137 ++++++++++++++++++++++++++++------------------------
1 file changed, 74 insertions(+), 63 deletions(-)

diff --git a/gdb/solib.c b/gdb/solib.c
index 1ba98137f5e..d641a24dc86 100644
--- a/gdb/solib.c
+++ b/gdb/solib.c
@@ -1010,84 +1010,61 @@ solib_add (const char *pattern, int from_tty, int readsyms)
}
}

-/* Implement the "info sharedlibrary" command. Walk through the
- shared library list and print information about each attached
- library matching PATTERN. If PATTERN is elided, print them
- all. */
+/* Helper function for "info sharedlibrary" and "info namespace".
+ This receives a list of solibs to be printed, and prints a table
+ with all the relevant data. If PRINT_NAMESPACE is true, figure out
+ the solib_ops of the current gdbarch, to calculate the namespace
+ that contains an solib.
+ Returns true if one or more solibs are missing debug information,
+ false otherwise. */

static void
-info_sharedlibrary_command (const char *pattern, int from_tty)
+print_solib_list_table (std::vector<const solib *> solib_list,
+ bool print_namespace)
{
- bool so_missing_debug_info = false;
- int addr_width;
- int nr_libs;
gdbarch *gdbarch = current_inferior ()->arch ();
- struct ui_out *uiout = current_uiout;
-
- if (pattern)
- {
- char *re_err = re_comp (pattern);
-
- if (re_err)
- error (_ ("Invalid regexp: %s"), re_err);
- }
-
/* "0x", a little whitespace, and two hex digits per byte of pointers. */
- addr_width = 4 + (gdbarch_ptr_bit (gdbarch) / 4);
-
- update_solib_list (from_tty);
-
- /* ui_out_emit_table table_emitter needs to know the number of rows,
- so we need to make two passes over the libs. */
+ int addr_width = 4 + (gdbarch_ptr_bit (gdbarch) / 4);
+ const solib_ops *ops = gdbarch_so_ops (gdbarch);
+ struct ui_out *uiout = current_uiout;
+ bool so_missing_debug_info = false;

- nr_libs = 0;
- for (const solib &so : current_program_space->solibs ())
- {
- if (!so.so_name.empty ())
- {
- if (pattern && !re_exec (so.so_name.c_str ()))
- continue;
- ++nr_libs;
- }
- }
+ /* There are 3 conditions for this command to print solib namespaces,
+ first PRINT_NAMESPACE has to be true, second the solib_ops has to
+ support multiple namespaces, and third there must be more than one
+ active namespace. Fold all these into the PRINT_NAMESPACE condition. */
+ print_namespace = print_namespace && ops->num_active_namespaces != nullptr
+ && ops->num_active_namespaces () > 1;

- /* How many columns the table should have. If the inferior has
- more than one namespace active, we need a column to show that. */
int num_cols = 4;
- const solib_ops *ops = gdbarch_so_ops (gdbarch);
- if (ops->num_active_namespaces != nullptr
- && ops->num_active_namespaces () > 1)
+ if (print_namespace)
num_cols++;

{
- ui_out_emit_table table_emitter (uiout, num_cols, nr_libs,
+ ui_out_emit_table table_emitter (uiout, num_cols, solib_list.size (),
"SharedLibraryTable");

/* The "- 1" is because ui_out adds one space between columns. */
uiout->table_header (addr_width - 1, ui_left, "from", "From");
uiout->table_header (addr_width - 1, ui_left, "to", "To");
- if (ops->num_active_namespaces != nullptr
- && ops->num_active_namespaces () > 1)
+ if (print_namespace)
uiout->table_header (5, ui_left, "namespace", "NS");
uiout->table_header (12 - 1, ui_left, "syms-read", "Syms Read");
uiout->table_header (0, ui_noalign, "name", "Shared Object Library");

uiout->table_body ();

- for (const solib &so : current_program_space->solibs ())
+ for (const solib *so : solib_list)
{
- if (so.so_name.empty ())
- continue;
-
- if (pattern && !re_exec (so.so_name.c_str ()))
+ if (so->so_name.empty ())
continue;

ui_out_emit_tuple tuple_emitter (uiout, "lib");

- if (so.addr_high != 0)
+ if (so->addr_high != 0)
{
- uiout->field_core_addr ("from", gdbarch, so.addr_low);
- uiout->field_core_addr ("to", gdbarch, so.addr_high);
+ uiout->field_core_addr ("from", gdbarch, so->addr_low);
+ uiout->field_core_addr ("to", gdbarch, so->addr_high);
}
else
{
@@ -1095,12 +1072,11 @@ info_sharedlibrary_command (const char *pattern, int from_tty)
uiout->field_skip ("to");
}

- if (ops->num_active_namespaces != nullptr
- && ops->num_active_namespaces ()> 1)
+ if (print_namespace)
{
try
{
- uiout->field_fmt ("namespace", "[[%d]]", ops->find_solib_ns (so));
+ uiout->field_fmt ("namespace", "[[%d]]", ops->find_solib_ns (*so));
}
catch (const gdb_exception_error &er)
{
@@ -1109,33 +1085,68 @@ info_sharedlibrary_command (const char *pattern, int from_tty)
}

if (!top_level_interpreter ()->interp_ui_out ()->is_mi_like_p ()
- && so.symbols_loaded && !objfile_has_symbols (so.objfile))
+ && so->symbols_loaded && !objfile_has_symbols (so->objfile))
{
so_missing_debug_info = true;
uiout->field_string ("syms-read", "Yes (*)");
}
else
- uiout->field_string ("syms-read", so.symbols_loaded ? "Yes" : "No");
+ uiout->field_string ("syms-read", so->symbols_loaded ? "Yes" : "No");

- uiout->field_string ("name", so.so_name, file_name_style.style ());
+ uiout->field_string ("name", so->so_name, file_name_style.style ());

uiout->text ("\n");
}
}

- if (nr_libs == 0)
+ if (so_missing_debug_info)
+ uiout->message (_ ("(*): Shared library is missing "
+ "debugging information.\n"));
+}
+
+/* Implement the "info sharedlibrary" command. Walk through the
+ shared library list and print information about each attached
+ library matching PATTERN. If PATTERN is elided, print them
+ all. */
+
+static void
+info_sharedlibrary_command (const char *pattern, int from_tty)
+{
+ struct ui_out *uiout = current_uiout;
+
+ if (pattern)
+ {
+ char *re_err = re_comp (pattern);
+
+ if (re_err)
+ error (_ ("Invalid regexp: %s"), re_err);
+ }
+
+ update_solib_list (from_tty);
+
+ /* ui_out_emit_table table_emitter needs to know the number of rows,
+ so we need to make two passes over the libs. */
+
+ std::vector<const solib *> print_libs;
+ for (const solib &so : current_program_space->solibs ())
+ {
+ if (!so.so_name.empty ())
+ {
+ if (pattern && !re_exec (so.so_name.c_str ()))
+ continue;
+ print_libs.push_back (&so);
+ }
+ }
+
+ print_solib_list_table (print_libs, true);
+
+ if (print_libs.size () == 0)
{
if (pattern)
uiout->message (_ ("No shared libraries matched.\n"));
else
uiout->message (_ ("No shared libraries loaded at this time.\n"));
}
- else
- {
- if (so_missing_debug_info)
- uiout->message (_ ("(*): Shared library is missing "
- "debugging information.\n"));
- }
}

/* See solib.h. */
--
2.49.0